Check valves may be employed in any one of numerous situations. For example, check valves may be used in an air distribution system to control an amount of air that flows from one portion of an aircraft to another. In this regard, check valves may be disposed in a duct between an air source and one or more outlets for exhausting the received air to desired areas within the aircraft, such as, for example, to an aircraft cabin or an underfloor section of the aircraft.
One exemplary type of check valve that has been employed in aircraft is a split flapper check valve. A split flapper check valve typically includes a valve body, a pair of flappers, and a stop tube. The valve body is configured to be inserted into the air distribution system duct and includes an upstream side, a downstream side, and a pair of flow channels that extends between the upstream and downstream sides. A pair of stop supports extends axially away from the valve body, and the stop tube is coupled to and extends between the stop supports. The flappers are rotationally mounted on the valve body, and are moveable between closed and open positions to control flow through the flow channels.
Generally, split flapper check valve components are made of metallic materials. Consequently, when a sudden pressure change occurs and the flappers and stop tube contact each other, they may produce a relatively loud noise. During flight, the noise may be audible to passengers in the aircraft, which may not be desirable.
Accordingly, there is a need to reduce noise produced when the flappers and stop tube of a split flapper check valve contact each other. In addition, there is a need for split flapper check valve that is lightweight and relatively inexpensive to implement. Furthermore, other desirable features and characteristics of the present invention will become apparent from the subsequent detailed description and the appended claims, taken in conjunction with the accompanying drawings and the foregoing technical field and background